Abstract: An image projector apparatus, for cinematograph film or the like transparent frames, includes a programmable control for instance operable from magnetic tape which may include audio signals stored in synchronism with the intended speed of transport of the frames by the projectors; more than one series of images, e.g. on two cinematograph films for superposed projection, are described and the projection dwell period for each image, in a series alternating with transport from frame to frame, is sustained over a broad range of image series speeds, e.g. normal slow-motion or accelerated viewing speeds.